Pseudobactin biogenesis in the plant growth-promoting rhizobacterium Pseudomonas strain B10: identification and functional analysis of the L-ornithine N(5)-oxygenase (psbA) gene.

ABSTRACT: Pseudobactin(B10), the fluorescent siderophore produced by the rhizobacterium Pseudomonas strain B10, contains the hydroxamate ligand D-N(5)-hydroxyornithine (D-N(5)-OH-Orn). We cloned the L-Orn N(5)-oxygenase (psbA) gene from a genomic library of Pseudomonas strain B10 and demonstrated that PsbA is involved in the conversion of L-Orn to its N(5)-OH derivative. PsbA shows significant similarity to microbial omega-amino acid hydroxylases containing flavin adenine dinucleotide and NADP cofactor-binding sites and the FATGY signature of the putative substrate recognition pocket. The psbA gene is monocistronic, and its transcription is negatively controlled by iron. A site-specific psbA mutant of Pseudomonas strain B10 was biochemically complemented with the precursor L-N(5)-OH-Orn, suggesting

SUBMITTER: Ambrosi C 

PROVIDER: S-EPMC94761 | biostudies-literature | 2000 Nov

REPOSITORIES: biostudies-literature